Anti-water-hammer device



F6). i SHAFF ANTI-WATER HAMMER DEVICE Filed Sept; 15, 1945 INVENTOR..Hazmn Shaft. 41 I Mm v ATTORNEY? Patented Feb. 18, 1947 1 Claim.

My invention relates to devices for eliminating the pounding phenomenaobserved in water systems, popularly known as water hammering. Thisphenomena is the result of a disturbance more or less violent whichtakes place in water pipes from the sudden closing of the taps or valvesin the system. The sudden closing, stops the onrushing water in thesystem, and the energy of the moving water expiates itself in producinga water hammer which is annoying, as well as damaging to the water pipesystem. The resulting strain tends to loosen fittings and connectionsand sometimes produces a breaking in the system.

It is known in the art that the water hammer and its effects may, in ameasure, be mitigated by providing at some preferred point in the systema sealed air chamber, connecting with the pipes of the system itself theair in the air chamber acting as a cushion or shock absorber, permittingthe onrushing water, when the tap or valve is suddenly closed, to spendits momentum in compressing the air of the air chamber.

In devices of this character, it is important that for the continuousand efficient working of the air chamber that it contain an adequate aircushion at all times.

In the current practice in the art, however, the air cushion in thecourse of use is relatively quickly absorbed or entrapped in the waterof the system, rendering the air chamber ineffective to prevent waterhammering. The air chamber becomes water logged, the water in the systemgradually rising to fill it and replacing the air cushion which isessential to practical use. In current devices, it is necessary tocompletely remove the same frequently, and either replace the same, orto recondition the same for further use. This necessitates the use ofskilled plumbing help and consequent expense and the temporary closingof the water supply with resulting inconvenience.

My invention has for its object the provision of means lor cushioningand absorbing the shock produced by the water phenomenon known as waterhammering, in which means are provided for assuring an adequate aircushion in the air chamber under all circumstances of use.

Another object of my invention is to provide a device containing an airchamber, with means for easily replenishing the air which may beabsorbed or entrapped therefrom in use, without the need of removing thedevice.

Another object of my invention is to provide an improved device of thekind mentioned, in which the air cushion in the air chamber may bereadily and quickly replenished when dissipated, without the need ofremoving the device or stopping the flow of water in the system.

Another object of my invention is to provide a simple device of the kindin question which may be readily and quickly reconditioned for use bythe average householder without resort to skilled plumbing help.

My invention also has for its object such other advantages ashereinafter are made to appear.

It will be obvious to those versed in the art to which my inventionrelates that the same may be incorporated in several differentconstructions. The accompanying drawing is submitted therefore for thepurpose of showing the preferred embodiment of my invention whereby thedisadvantages current in the art may be obviated in which Fig. l is anelevated view in perspective showing the combination of parts enteringinto my invention. Fig. 2 is a fragmentary and enlarged section of Fig.1, taken along line 22, viewed in the direction of the arrow, showingthe air intake valve, and the water drain valve in section. Fig. 3 is asection in elevation of Fig. 2, taken along line 3-3 of Fig. 2, viewedin the direction of the arrow, showing the water intake valve and airintake valve in section.

Similar numerals refer to similar throughout the several views.

My invention is also in the combination and arrangement of parts and inthe construction as herein set forth and claimed.

Referring more particularly to the drawing, Fig. 1 represents ananti-water hammer device embodying my invention in perspective showingthe relation of the various parts. The device has an air chamber a,sealed at the top by cap I and at the bottom by cap 8. The air chamberand associated parts are preferably made of brass or bronze but anyother type of material may be used provided it is capable ofwithstanding the ressures of the Water systems to which it is applied.Leading into the air chamber is valve 9, having its inlet 9, afiixedairtight to cap 1, and its outlet ill. Valve key M operates to open andclose valve Leading into the air chamber through the bottom cap 8, isvalve i2, having its inlet I3, afiixed airtight to cap 8. Valve key I!serves to open and close valve 12. Leading out of valve 52 is drainvalve M, it being secured airtight to valve :2. Turn cap 86 serves toshut and open drain valve i l.v

In Fig. 3 the air inlet valve 9 is shown in detail. At its end it entersair chamber 6 through parts neck 9. The upper part of neck 9' is shapedconcave to form a valve seat H, to receive the lower correspondingconcave end I I of valve key ll. Valve key H is threaded at H", and isscrewed into corresponding threads cut in the upper portion of the boreof valve 9.

Valve key I l is square shaped at its top to receive key 31 which isadapted to screw valve key H to fit tight into valve seat l when thevalve is to be closed, and to unscrew valve key ll away from seat l5when the valve is to be open.

The water inlet valve 12 is a modified globe valve, adapted to theobjects of the invention. Its body is securely and airtightedly aiiixedto the bottom cap 3. Valve I 2 has a neck It. End 36 is threaded andadapted to be connected on to the water system 38, one means ofconnection being shown as comprising threaded pipe 40 and T connection39. Within the valve body 12 and integral therewith are walls 2l,and 28dividing the valve body into sections 24 and 25, each opening into theother through a circular aperture 26. The walls 2! and 28 constitute onecontinuous dividing section in the center of which is aperture 26. Thearea of walls 2? and 28 adjacent the aperture are ground to form acontinuous valve seat 28, which is adapted to receive valve key 29.Valve key 28 terminates in an enlarged section 22 adapted to receivesecurely a washer 23. The valve key 25, is enlarged to form a threadedportion 25' which screws in and out of corresponding threads in casing18 which surrounds and keeps valve key 28 in position. Casing 18 isscrewed onto neck I9 of valve body IE to form a water tight joint, andthe key passing through casing 58 is packed to render the casingsurrounding it water tight. By operation of wheel ll affixed to valvekey 20, washer 23 is brought to bear against valve seat 28' closingaperture 26, or is removed therefrom to open said aperture permittingthe water supply to be cut oil or to enter the air chamber. When thevalve is closed the water from the water system 38 enters. section 24 ofvalve body i2, being completely shut off from the air chamber. Whenvalve is open the water in the water system 38 rises further passingthrough the aperture 26, enters section 25, and continues to rise in airchamber 6 until the pressure reaction of the air enclosed in the airchamber becomes equal to the water pressure. In Fig. 3 the water isshown as 29.

In Fig. 2, there is shown the parts of drain valve l4 and its relationto the water inlet valve i2. A cross section along line 22 of Fig. 1 isshown. Drain valve I l enters into valve 12, through a hollow neck 33which is secured into the body of valve 44 airtight and opens intosection 25 of valve body [2. Neck 33, bears threads 31, and its end isground smooth to serve as a valve seat 33'. Turn cap i6 is threadedwithin, the thread corresponding to threads 3i, being adapted to screwon to the threaded portion of neck 33. The inside of turn cap I6 isground flat and adapted to correspond with valve seat 33 when screweddown against valve seat 33' to form an air tight valve. Washer 34 servesto assure a water tight valve. Turn cap it has bored through its sideaperture it. When turn cap i6 is unscrewed away from valve seat 33'suiliciently the valve is opened and water is permitted to pass throughneck 33 and to drain out of aperture iii.

In operation my invention functions in the following manner. Ata chosenpoint in the water system 38, my device is aifixed, one way of aflixingthe same being shown in Figure 1. The water inlet valve I2 and drainvalve Id are each securely closed, and the air intake valve 9 is openprior to afiixing the device to the water system.

To place the device in operation key 31 is turned to securely close airintake valve 9, air chamber 6 being full with air at atmosphericpressure. Then valve i 2 is opened and the water in the water system 38enters through section 24, passes through aperture 26, then into section25, and rises in the air chamber until the air pressure in the airchamber balances the water pressure. The result is an air cushion in theair chamber. The device is now part of the water system and is adaptedto obviate water hammering and to readily furnish under allcircumstances of use a readily available air cushion, easily and quicklyreplenished when diminished by water absorption or other means. There isno need for removing the device once aifixed, the air being replenishedby the simple arrangement of parts as disclosed.

In the course of use of my invention when water hammering is againnoted, it is indicative of a need for more air in the air chamber, thatin the course of use the air has been absorbed or entrapped so thatthere is not a sufiicient air cushion to operate as a shock absorber. Inthat event my invention permits the following means of replenishing theair cushion without disturbing the flow of water in the system itselfand without the need of removing the device nor the need of skilledadjustment. The device may by my simple arrangement of parts be put intouse within a few minutes whereas in the current art, a considerablelength of time will elapse before other devices can be readjusted to useagain.

In restoring my device'to its original state, I first close valve i2 byturning key 20 by means of wheel ll against valve seat 28, closingaperture 25. This shuts oh the water from the air chamber 6. I then opendrain valve M by unscrewing cap l 6, and open air valve 9. The action ofthese two valve openings is to permit the water to quickly drain out ofthe air chamber. When completely drained, which is a matter of a fewminutes, I close valve is, airtight again and then close valve Qairtight. This leaves the air chamber full of air at atmosphericpressure as originally. I then open valve i2 permitting the water in thewater system to again rise into the air chamber until the reaction ofthe air under pressure equals the water pressure. A sufficient aircushion results. The device is again ready for normal use. It is thusapparent what advantageous purposes my invention serves, and the easewith which it may be made to function over a long period of time, underall circumstances of use.

It will be obvious to those skilled in the art to which my inventionrelates that the same may be made in several different constructionsalthough my invention is described with a great degree of particularity.My showing is to exemplify merely the preferred embodiment of myinvention. For example, in place of the globe valve used as a Waterintake valve, a gate valve or similar valve may be used, and in place ofthe needle valve used for air intake or the drain valve asshown, othervalves may be used Without departing from the essence of my invention.

Various changes in the form, properties, and the details of constructionmay be resorted to without departing from the principle of sacrificingany of the advantages of this invention.

Having thus described my invention, I claim:

A device for eliminating water hammer in systems conducting fluids underpressure, having an air chamber and an air cushion therein; meansadapted for aifixing the air chamber to said system; valve meanscomprising a valve seat, and a valve key to operate said valve, sealedto and opening into said air chamber, adapted for making said airchamber accessible to the fluid in said system, to permit said fluid toenter said air chamber and compress the air cushion therein, undernormal circumstances of use, and adapted to shut off said air chamberfrom the fluid in said system when the air cushion therein is to bereplenished; valve means, comprising a valve seat, and a valve key tooperate said valve, sealed to and opening into the upper portion of saidair chamber, adapted to allow the air from without to communicate withthe air within said air chamber when said air chamber remains shut 01fREFERENCES CITED The following references are of record in the file ofthis patent:

UNITED STATES PATENTS Number Name Date 1,525,517 Smith Feb. 10, 19251,950,107 Guinn Mar. 6, 1934 2,220,079 Cornell Nov. 5, 1940

